/*
vector <char> A[1e6+5];
vector <int> idx[1e6+5];
idx = -1;
stack <pair <char, int> > Ins;
*/
#include <bits/stdc++.h>
using namespace std;
struct Instruction {
char type;
int prev, x;
Instruction() {};
Instruction(char cc, int a1, int a2) {
type = cc;
prev = a1;
x = a2;
}
};
vector <Instruction> Ins;
vector <char> A;
int idx = -1;
void Init() {
//for (int i=0; i<1e6+5; i++) idx[i] = -1;
for (int i=0; i<1e6+5; i++) A.push_back(-1);
}
void TypeLetter(char L) {
idx++;
//int anterior = A[idx];
A[idx] = L;
//Ins.push_back(Instruction('T', anterior, L);
}
void ReverseType(Instruction it) {
A[idx] = it.prev;
}
void ReverseUndone(int u) {
idx += u;
}
void UndoCommands(int u) {
idx -= u;
}
char GetLetter(int p) {
return A[p];
}
